a) Field of the Invention
The present invention is directed to compounds useful as probes for characterizing and studying the adenosine A.sub.2 receptor. The present invention is also directed to methods of treating central nervous system disorders and cardiovascular disorders which include treating hypertension and thrombosis by administering said compounds.
b) Description of Related Art
Adenosine acts as a modulator of activity in the cardiovascular system, central nervous system, immune system, and other physiological systems. Adenosine receptors are subdivided into two subclasses; the A.sub.1 - and the A.sub.2 -receptors, which are in general inhibitory and stimulatory, respectively, towards adenylate cyclase.
A.sub.2 -adenosine receptors mediate the following physiological effects of adenosine: the inhibition of platelet aggregation, immunosuppression, vasodilation, and anti-psychotic like actions.
EP-A 354,180 discloses certain imidazo [4,5-b] pyridine derivatives which exhibit pharmacological properties as A.sub.2 -receptor antagonists and the preparation thereof. These compounds differ from the present compounds as the present compounds make use of a lower alkyl diamine moiety bound to a carboxy group, which is active alone or can be then derivatized with other compounds, e.g. compounds having acyl radicals which are in turn also active at the adenosine A.sub.2 receptor.